Critical Remote Code Execution Vulnerability in vLLM via Mooncake Integration

This security issue gives an attacker the ability to remotely execute code on vLLM deployments using the Mooncake feature by sending a specially crafted payload that exploits an unsafe deserialization process. The following protection guardrails can further prevent the following steps an attacker can take: Initially, an attacker would send malicious data designed to be processed by Python's pickle.loads() function; Python Deserialization Protection directly counters this by intercepting the deserialization attempt and applying security policies to block the execution of harmful function calls embedded within the attacker's payload, thus preventing the initial remote code execution. Should an attacker somehow achieve code execution and the malicious code attempts to run operating system commands for reconnaissance (like gathering system information using uname or whoami) or to manipulate files (such as compressing model data for exfiltration using tar), Python OS Command Injection Prevention would monitor the Python runtime and block these unauthorized OS command execution attempts. To establish persistent control, an attacker might then try to create a reverse shell, connecting the compromised system back to their command-and-control server; Reverse Shell Protection is designed to detect and prevent this by blocking attempts to bind shell file descriptors to network sockets. If the vLLM service is running in a containerized environment and the attacker, having gained code execution, attempts to download and run new tools not part of the original container image—such as a more robust backdoor, a network scanning utility to find other vulnerable hosts, or a data exfiltration tool like rclone—Container Drift Protection (Binaries & Scripts) would block the execution of these unauthorized binaries or scripts. Furthermore, if the attacker's code execution involves placing a malicious script or executable in a non-standard directory like /tmp and then attempting to run it, Process Path Exec Allow would intercept this execution attempt and block it if the path is not on an approved allowlist, preventing the attacker from running tools from unexpected locations.

• T1059.006: Command and Scripting Interpreter: Python: The vulnerability in vLLM via Mooncake integration allows attackers to execute remote code by exploiting an unsafe deserialization process. The use of pickle.loads() for deserializing network data is the core issue, which aligns with the MITRE ATT&CK technique for exploiting deserialization vulnerabilities to execute arbitrary code. This technique is identified as T1059.006 (Command and Scripting Interpreter: Python).
• T1590: Gather Victim Network Information: The article mentions that the Mooncake integration exposes sockets on all interfaces without network controls, allowing arbitrary users to send payloads to the affected service. This indicates a lack of proper network segmentation and filtering, which is relevant to the MITRE ATT&CK technique T1590 (Gather Victim Network Information) as attackers can exploit network configurations to identify vulnerable services.
• T1040: Network Sniffing: The network exposure of the Mooncake pipe using ZMQ over TCP suggests that attackers could potentially perform network sniffing or traffic analysis to gather information about the communication protocols and data being transmitted. This aligns with MITRE ATT&CK technique T1040 (Network Sniffing).
• T1570: Lateral Tool Transfer: The vulnerability allows for remote code execution on distributed hosts, indicating that attackers could use this to move laterally across the network. This aligns with the MITRE ATT&CK technique T1570 (Lateral Tool Transfer), as attackers could transfer tools or payloads across the network using the compromised service.

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